#) Reverse Osmosis: Reverse osmosis (RO) is a water purification technology that uses a semipermeable membrane.
(*) This membrane technology is not properly a filtration method. In reverse osmosis, an applied pressure is used to overcome osmotic pressure, a colligative property, that is driven by chemical potential, a thermodynamic parameter.
(*) Reverse osmosis can remove many types of molecules and ions from solutions, and is used in both industrial processes and the production of potable water.
(*) The result is that the solute is retained on the pressurized side of the membrane and the pure solvent is allowed to pass to the other side.